How to create a namespace in a project? (not via the UI.)

Hi,

I have raised this as a bug, located here: https://github.com/rancher/rancher/issues/23376

in short we have some yaml files which we want to rancher kubectl apply -f ., on these files: https://github.com/dbones-simple-shop/infra/tree/master/k8s

however when we run the namespace one, it does not add the namespace to the current scoped project

apiVersion: v1
kind: Namespace
metadata:
  name: data

how are we programmatically meant to create a namespace in a project?